Apparatus for damping vibrations

Abstract

Apparatus for damping vibrations between the output element of the engine and the power train in a motor vehicle has flywheels which are rotatable relative to each other. One flywheel is mounted on the output element of the engine and another flywheel is connectable to the power train by a friction clutch. Vibration dampers are installed between the flywheels, and such dampers are confined in a housing which is provided on the one flywheel and contains a supply of viscous fluid medium for the parts of the dampers. The housing is the input member of the dampers and the output member of the dampers is a flange which extends into the housing and is axially movably coupled to the other flywheel.

We claim: 
     
       1. Apparatus for damping vibrations, comprising at least two flywheel elements which are mounted for rotation relative to each other and include a first flywheel element connectable with a prime mover and a second flywheel element connectable with a transmission by way of a clutch; and damper means interposed between said flywheel elements and including at least two resilient dampers operating in parallel, one of said at least two resilient dampers being arranged to oppose, alone, a first stage of rotation of said first and second flywheel elements from a starting position and the other of said at least two resilient dampers being arranged to oppose, with said one resilient damper, a next-following second stage of rotation of said first and second flywheel elements relative to each other, said one resilient damper having a first stiffness and said other resilient damper having a second stiffness greater than said first stiffness. 
     
     
       2. The apparatus of claim 1, wherein said flywheel elements and said damper means form part of a power train in a motor vehicle, said power train comprising an engine constituted by said prime mover and said power train further comprising a gearbox constituted by said transmission. 
     
     
       3. The apparatus of claim 1, wherein said clutch includes a friction clutch which is engageable to transmit torque between said second flywheel element and said transmission. 
     
     
       4. The apparatus of claim 1, wherein said at least two flywheel elements are rotatable about a common axis, said one resilient damper being disposed at a first radial distance from said axis and said other resilient damper being disposed at a lesser second radial distance from said axis, said other resilient damper including compressible coil springs each having neighboring convolutions and said neighboring convolutions abutting each other to prevent further compression of said coil springs in response to a predetermined rotation of said first and second flywheel elements relative to each other from said starting position. 
     
     
       5. The apparatus of claim 1, wherein said one resilient damper and said other resilient damper respectively comprise first and second input portions, said second input portion being rotatable within limits relative to said first input portion about a common axis of said flywheel elements. 
     
     
       6. The apparatus of claim 5, wherein said second input portion forms part of one of said flywheel elements. 
     
     
       7. The apparatus of claim 6, wherein said resilient dampers have a common output portion connected with the other of said flywheel elements. 
     
     
       8. The apparatus of claim 1, wherein said flywheel elements are rotatable about a common axis and one of said flywheel elements includes portions defining at least one annular chamber having a radially inner portion nearer to said axis and a closed radially outer portion more distant from said axis, said resilient dampers including a first resilient damper disposed at a first radial distance from said axis and a second resilient damper disposed in said at least one chamber at a greater second radial distance from said axis, and further comprising a supply of viscous fluid at least partially filling said at least one chamber. 
     
     
       9. The apparatus of claim 8, wherein said fluid includes a lubricant. 
     
     
       10. The apparatus of claim 8, wherein said first resilient damper and said second resilient damper are disposed in said at least one chamber. 
     
     
       11. The apparatus of claim 1, wherein one of said flywheel elements defines at least one annular chamber spacedly surrounding a common axis of said flywheel elements and receiving at least a portion of each of said resilient dampers, said resilient dampers having output portions extending into said at least one chamber radially outwardly away from said axis. 
     
     
       12. The apparatus of claim 1, wherein said resilient dampers include a resilient damper nearer to and a resilient damper more distant from a common axis of said flywheel elements, said nearer resilient damper including input and output portions having windows for resilient elements of said nearer resilient damper, said resilient elements being received in the respective windows at least substantially without play as seen in a circumferential direction of said flywheel elements. 
     
     
       13. The apparatus of claim 1, wherein one of said flywheel elements defines an annular chamber spacedly surrounding a common axis of said flywheel elements, said one flywheel element including an annular intermediate portion surrounding said chamber and two walls flanking said chamber as seen in the direction of said axis and extending from said intermediate portion substantially radially inwardly toward said axis, said resilient dampers including a first resilient damper nearer to said axis and a second resilient damper more distant from said axis, said more distant second resilient damper being disposed in said chamber adjacent said intermediate portion, said resilient dampers including an output portion disposed between said walls as seen in the direction of said axis. 
     
     
       14. The apparatus of claim 13, wherein one of said walls includes a substantially radial flange of said one flywheel element. 
     
     
       15. The apparatus of claim 14, wherein the other of said walls is disposed between said one wall and other of said flywheel elements. 
     
     
       16. The apparatus of claim 13, wherein said annular intermediate portion is part of and extends from one of said walls in the direction of said axis. 
     
     
       17. The apparatus of clam 13, wherein said annular intermediate-portion is of one piece with one of said walls and is secured to the other of said walls, said other wall including a washer-like portion extending from said intermediate portion substantially radially inwardly toward said axis. 
     
     
       18. The apparatus of claim 1, wherein one of said flywheel elements defines an annular chamber spacedly surrounding a common axis of said flywheel elements and said one flywheel element includes two walls flanking said chamber, at least a portion of at least one of said resilient dampers being confined in said chamber. 
     
     
       19. The apparatus of claim 18, wherein said portion of said at least one resilient damper in said chamber includes energy storing elements and said walls have pockets for portions of said energy storing elements, said pockets extending substantially axially of said flywheel elements and including radially outer portions snugly receiving the respective energy storing elements. 
     
     
       20. The apparatus of claim 19, wherein said walls have surfaces bounding said pockets and said energy storing elements abut said surfaces at least under the action of centrifugal force in response to rotation of said flywheel elements. 
     
     
       21. The apparatus of claim 20, wherein each pocket of one of said walls is located opposite to and communicates with a pocket of the other of said walls, said communicating pockets defining for said energy storing elements receptacles having a substantially circular cross-sectional outline. 
     
     
       22. The apparatus of claim 1, wherein said flywheel elements are rotatable about a common axis and one of said flywheel elements defines an annular chamber spacedly surrounding said axis and confining at least a portion of at least one of said resilient dampers, said one flywheel element including two walls flanking said chamber and further comprising means for sealing said chamber, said sealing means including a diaphragm spring interposed between one of said walls and a substantially washer-like member affixed to the other of said flywheel elements. 
     
     
       23. The apparatus of claim 1, wherein one of said flywheel elements includes two walls extending substantially radially of a common axis of said flywheel elements and flanking an annular chamber receiving at least a portion of at least one of said resilient dampers, said portion of said at least one resilient damper including neighboring arcuate energy storing elements extending circumferentially of said one flywheel element and disposed in confronting circumferentially complete annular pockets provided in said walls, said at least one resilient damper further comprising abutments provided in said pockets between said energy storing elements. 
     
     
       24. The apparatus of claim 23, wherein said abutments include rivets. 
     
     
       25. The apparatus of claim 1, wherein said resilient dampers include a first resilient damper more distant from a common axis of said flywheel elements and a second resilient damper nearer to said common axis, said resilient dampers having a common output portion and said second resilient damper having an input portion centering said common output portion. 
     
     
       26. The apparatus of claim 1, wherein said resilient dampers include a first resilient damper more distant from a common axis of said flywheel elements and a second resilient damper nearer to said common axis, said first resilient damper including energy storing elements extending circumferentially of said flywheel elements along an arc of at least 45 degrees. 
     
     
       27. The apparatus of claim 26, wherein said arc is at least close to 110 degrees. 
     
     
       28. The apparatus of claim 1, wherein said resilient dampers include a first resilient damper more distant from a common axis of said flywheel elements and a second resilient damper nearer to said common axis, said first resilient damper including at least three energy storing elements extending substantially circumferentially of said flywheel elements. 
     
     
       29. The apparatus of claim 28, wherein said first resilient damper comprises four energy storing elements. 
     
     
       30. The apparatus of claim 1, wherein said resilient dampers include a first resilient damper more distant from a common axis of said flywheel elements and a second resilient damper nearer to said common axis, said first resilient damper being arranged to transmit a first maximum torque between said flywheel elements and said second resilient damper being arranged to transmit between said flywheel elements a second maximum torque greater than said first maximum torque.